HOUSTON (KIAH) – A very warm weather pattern takes hold of much of the U.S. with temperatures reaching the 80s in the North, which is more than 20 degrees warmer than normal.

Temperatures compared to average Tuesday

Parts of South Dakota, for example, will be 10 degrees warmer than Houston with highs there in the mid 80s.

Forecast highs Tuesday

It’s that time of year when a heat wave like this can cause significant snowmelt that may lead to flooding, especially with some areas seeing a near-record amount of water stored in the snowpack. The National Weather Service has issued flood advisories in Montana, North Dakota, Minnesota and Wisconsin.

Forecast highs Wednesday